CSS Unit Converter — px, rem, em, vw, vh & More
Type a value in any CSS unit and see live conversions to px, rem, em, vw, vh, pt, pc, and cm. Set root font size and viewport for accurate relative units. No signup.
Keywords: css unit converter, px to rem, rem to px, px to em, css units, viewport units, web design calculator
Frequently Asked Questions
What units are supported?
px, rem, em, vw, vh, pt, pc (picas), and cm.
How are relative units calculated?
rem uses root font size, em uses parent font size, vw/vh use viewport dimensions — all configurable.
What are the default context values?
Root font: 16px, parent font: 16px, viewport: 1440×900 — matching typical browser defaults.